This study has been conducted in order to determine nutritional value and digestibility and
degradability of twigs in four tree species including Zelkova carpinifolia, Gleditchia caspica, Populus deltoids
and Quercus castanaefolia through chemical and gas production method using 3 fistulated sheep in National
Research Institute for Animal Science, Iran. The experiment conducted based on Randomized Complete Design
and obtained data were analyzed by software SAS and Neway. Chemical compounds (crude protein (CP),
Neutral Detergent Fiber (NDF), Acid Detergent Fiber (ADF), Ether Extract (EE), Ash, Crude Fiber (CF), NFC
(Non Fiber Carbohydrate), Nitrogen Free Extract (NFE) and organic material (OM) and degradation were
determined at the times of 0, 2, 4, 6, 8, 12, 24, 48, 72 and 96 h in gas production method and parameters such
as (OMD-SCFA-ME-NEL-CP-DMD) were determined. Amount of crude protein for 4 species are as follow:
(Z. carpinifolia (11%), G. caspica (15.4%), P. deltoids (10.3%) and Q. castanaefolia (9.5%)), also amount of
crude fiber in these trees are respectively 32.7, 18.6, 13.9 and 22.9%. The most and the least fermentation and
gas production was observed respectively in G. caspica and Z. carpinifolia. The most mount of gas production
belonged to G. caspica with 54 mL/g of dry matter at 96th h.

S. Lotfi, B. Rasouli, A.A. Ghotbi and H. Yosefifar, 2012. Determination of Nutritional Value and Digestibility of Twigs in Four Tree Species through Chemical and Gas Production Methods.
International Journal of Animal and Veterinary Advances, 4(2): 157-162.